O'Fallon (IL) Sunshine Hours by Month

The amount of sunshine is fundamental to comprehending a place's climate. This page shows the total number of hours of direct sunlight per month and the average hours per day in O'Fallon, Illinois, United States of America. The numbers reflect climate data gathered over a 30-year period, from 1990 to 2020.

Monthly hours of sunshine

Sunshine in O'Fallon varies greatly throughout the year. The sunniest month, July, reaches an impressive 311 hours, while December, the darkest month, offers only 128 hours. The total annual amount of sun is 2594 hours.

Daily hours of sunshine

Seasonal changes in sunshine hours are quite obvious in O'Fallon. While July receives considerable daily sunshine with up to 10.4 hours, December marks the darkest time of the year, where sunshine is scarce with only 4.3 hours of sunlight per day.

Average percent of sunshine

On average the sun shines 68% of the time during the day in July, the highest percentage of any month. December has the lowest percentage at 44%.

O'Fallon enjoys an average of 2594 hours of sunshine annually. Let’s compare this with some popular tourist destinations:

In Lisbon, Portugal, there are approximately 2801 hours of sunshine annually, highlighting its warm and sunny Mediterranean climate.

In contrast, Reykjavík, Iceland, receives only about 1330 hours of sunshine per year, known for its frequently overcast and rainy skies.

Beijing, China, has 2505 hours of sunshine annually, with clear, sunny days in winter.

Perth, Australia, enjoys 3180 hours of sunshine annually, the highest among major Australian cities.

June, O'Fallon’s wettest month, receives 102 mm (4 in) of rainfall and has a maximum daytime temperature of 30°C (86°F). During the driest month January you can expect a temperature of 5°C (41°F).

For more detailed insights into the city’s temperatures, check out our Temperature page. To explore more about precipitation patterns, visit our O'Fallon Precipitation page.